These experiments will study the behavioral events correlated with the firing of neurons and the firing repertoires of neurons in the hippocampus and retrohippocampal areas of unrestrained rats. Because of evidence that the behavioral events correlated with firing of neurons in hippocampus can change depending on the circumstances, and perhaps the salience of the cues, we will study the firing of the same neuron in three different situations: running an eight arm maze, performing a DRL-16 with schedule-induced polydipsia, and pup retrieval, all of which are disrupted by hippocampal lesions. These tasks were chosen to be able to look for spatial aspects and to test for relations to behaviors independent of the place where the rat is. They study both learned and unlearned behavior, and some behaviors occur in all three situations. We will look for features common to the three situations. In retrohippocampal areas, where the behavioral events correlated with firing and firing repertories of neurons have not been carefully studied before, the studies will primarily be a description with close attention to the anatomical location of the neurons. We will particularly look for relations to space, the slow wave theta rhythm, orienting behavior, slow wave sleep, REM sleep, unexpected events (or mismatch situations), and objects which are approached or avoided. All data will be computer processed to look for rates and patterns of firing, and reproducability of the firing across many trials.